Table 4

Different relation between HOMA-IR index and proinsulin metabolites in controls and
patients.

β coefficient (95% CI)

Intact proinsulin

Intact proinsulin/

Split proinsulin

Split proinsulin/

C-peptide ratio

C-peptide ratio

HOMA-IR index

Controls

4.02 (0.66-7.36)

6.23 (1.41-11.06)

10.95 (3.22-18.17)

14.84 (3.99-25.70)

Patients

0.97 (-0.11-2.06)

0.43 (-0.86-1.71)

6.98 (3.44-10.52)

5.83 (1.40-10.25)

P valuea

0.36

0.03

0.47

0.23

RA on GC

1.28 (-0.42-2.98)

0.39 (-1.66-2.44)

6.94 (3.38-10.50)

5.37 (1.06-9.69)

RA non on GC

0.74 (-0.82-2.28)

5.55 (-1.26-2.36)

4.95 (-1.29-11.18)

3.70 (-4.13-11.72)

P valueb

0.63

0.90

0.57

0.72

P value represents the comparison of β coefficient between controls and patients (a) and between RA on GC and RA not taking GCs (b) when interaction "HOMAIR × disease" is included in the regression model. HOMA-IR
index is considered an independent variable, and proinsulin metabolites as dependent
variables. Significant associations (P < 0.05) are depicted in bold